What Causes a Chicken to Lay a Soft Shell Egg?

It’s likely that you look forward to getting those lovely brown or white eggs from your hens every day. But once in a while you might find an egg with a strange shape and a soft, rubbery shell instead of the hard ones you’re used to. If you aren’t ready for them, these eggs with soft shells or no shells can be scary.

While an occasional soft-shelled egg from an otherwise healthy hen is usually not a cause for concern, repeated instances can signal an underlying issue that needs to be addressed. Read on to learn the most common causes of soft-shelled eggs so you can get your chickens laying perfect eggs once again.

Why Do Hens Lay Soft Shell Eggs?

Crystals of calcium carbonate are embedded in a protein matrix that makes up the shells of chicken eggs. This makes the shells hard and long-lasting, which keeps the egg inside safe. It’s important for an egg to stay in the shell gland or uterus for at least 20 hours while the shell forms around it.

Anything that interferes with this process can prevent a complete hard shell from forming. Let’s look at some of the most frequent culprits behind soft-shelled or shell-less eggs in backyard chickens.

Age of the Hen

A lot of the time, eggs with soft shells are caused by hens that are too old. As their reproductive systems get stronger, young pullets that are just starting to lay eggs often make eggs that are soft or don’t have the right shape at first. Like a young athlete learning a new sport, they are still working to get better at what they do.

As pullets enter peak laying age, their egg quality quickly improves. Give them a bit of grace and time to work out the kinks.

On the opposite end, senior hens may also start laying more soft or thin-shelled eggs as they age. Older hens tend to produce fewer eggs overall, so making each one can become more taxing on their bodies.

Stress

Another big reason why backyard chickens’ eggshells aren’t as good is stress. Anything that changes their routine or makes them feel threatened can make them stressed.

Examples include

• Extreme hot or cold weather
• Overcrowding
• Introduction of new flock members
• Predator attacks
• Excess activity from roosters
• Illness
• Change in diet or environment

Stress triggers the release of corticosterone, which causes the hen to mobilize calcium from her bones to deal with the perceived threat. This leaves less calcium available for proper eggshell formation.

Poor Nutrition

Nutritional deficiencies are a very common reason hens lay soft eggs. Producing an egg requires a tremendous amount of nutrients and energy from a hen’s body. Key nutrients for proper eggshell formation include:

• Calcium – The main structural component of the shell. Hens need about 4 grams of calcium carbonate per day.

• Vitamin D – Allows calcium absorption and metabolism. Lack of vitamin D leads to thin, weak shells.

• Phosphorus – Works with calcium to build strong bones and shells.

• Protein – Provides amino acids to form the shell matrix proteins.

• Vitamin C – Supports collagen formation.

Without adequate amounts of these nutrients in their diet, hens simply can’t create shells with the right thickness and strength. This results in soft, rubbery eggs that are prone to cracking and breaking.

Disease

Though not as common as the other causes, certain infectious diseases can also lead to reduced shell quality in backyard chickens.

For example, infectious bronchitis and Newcastle disease viruses can damage the hen’s oviduct where the shell forms. Parasites like roundworms rob nutrients as well.

If you notice other symptoms like coughing, sneezing, diarrhea, or lethargy along with soft eggs, disease may be the culprit. Consult a veterinarian for proper diagnosis and treatment.

How to Prevent Soft Shell Eggs

Now that you know why hens lay soft eggs, let’s go over some tips to help your flock lay perfect, strong shells again.

Ensure Adequate Calcium Intake

Calcium is by far the most important nutrient for proper eggshell formation. Each hen requires about 4 grams of calcium carbonate per day.

Ways to make sure they meet this requirement:

• Provide a complete layer feed: Most commercial feeds are balanced with calcium levels hens need.

• Offer free-choice calcium supplements: These come in the form of oyster shell, limestone chips, or crushed egg shells. Hens will consume what they need.

• Add calcium-rich treats: Snacks like yogurt, cheese, dark leafy greens, and mealworms boost calcium intake.

• Avoid calcium inhibitors: Foods high in oxalates like spinach and kale can block calcium absorption. Feed in moderation.

Monitor eggshell quality and adjust their calcium intake accordingly. Strong, heavy shells indicate sufficient levels.

Reduce Stress

Do your best to minimize anything in the hens’ environment that could trigger stress:

• Give them space: Allow at least 4 square feet per hen inside the coop and 8-10 square feet per bird in the run.

• Add shade and ventilation: Ensure the coop stays cool in summer and dry in winter.

• Discourage predators: Secure housing and runs to keep hens feeling safe.

• Separate aggressive roosters: Over-breeding stresses hens and causes injury.

• Quarantine new birds: Slowly introduce newcomers over 2 weeks to avoid disrupting flock dynamics.

The more you can reduce stressors and keep a predictable routine, the better your hens will produce.

Offer a Balanced Diet

In addition to calcium, make sure your chickens’ diet provides all the key nutrients needed for prime egg production:

• Quality protein sources: Meat meal, soybean meal, insects etc. Large amounts are needed to form the proteins in egg whites.

• Grains for energy: Corn, wheat, barley, oats give hens the calories and carbs they need.

• Vitamins and minerals: A complete feed, treats, and supplements cover needs for phosphorus, magnesium, selenium, vitamins D, E, A, and B12.

• Variety: Give free-choice treats and fresh forage when possible for a diverse nutrient intake.

If possible, have your chickens’ feed analyzed annually to ensure proper nutrition. A local extension office can help with testing.

Check for Illness

Keep a close eye on your flock for any signs of sickness, such as:

• Respiratory issues – coughing, sneezing, discharge
• Diarrhea
• Weight loss
• Lethargy
• Decreased appetite

Isolate any chickens showing symptoms and contact a poultry vet if needed. Treating the illness should resolve the egg problems.

With a few adjustments to their care, housing, and diet, your chickens should be back to laying gorgeous strong-shelled eggs in no time. But the occasional soft egg from an otherwise healthy hen is normal too. Don’t stress too much if it happens infrequently – just enjoy those funky looking eggs!

FAQs About Soft Shell Chicken Eggs

Are soft eggs safe to eat?

Soft-shelled eggs are prone to bacterial contamination and spoilage, so it’s best not to eat them. The weak shells allow bacteria to enter the egg contents more easily. Cook them fully for pets or discard soft eggs to be safe.

How long does it take a hen to form an egg shell?

The egg shell forms in the shell gland (uterus) during the last 12-20 hours of egg production. It starts as a thin membrane, then deposits layers of calcium carbonate crystals to reach its final thickness before the egg is laid.

Do roosters affect egg shell quality?

Overactive roosters that constantly mate with hens can contribute to stress, feathers loss, and injury. This distracts hens from eating and resting, which can impact shell quality. Separate roosters or allow at least 10 hens per rooster.

Can soft shelled eggs make chickens sick?

Soft eggs left in the nest can sometimes crack or break open, leaving the hen vulnerable to bacterial infection. It’s best to remove and discard any soft eggs promptly. But eating their own soft eggs generally won’t make healthy chickens sick.

How much calcium does a chicken need to lay eggs?

On average, a laying hen needs about 4 grams of calcium carbonate per day to produce eggs with strong shells. This equals about 56 grams per ounce of eggs laid. They get calcium from their feed, free-choice supplements, treats, and foraging.

The Take-Away on Soft Eggs

While frustrating to deal with, soft-shelled chicken eggs are a common and manageable problem for most backyard flocks. More often than not, issues like stress, nutrition, or illness are the underlying causes.

By making sure your hens have a balanced diet with adequate calcium, live in low-stress housing, and receive prompt veterinary care when sick, you can get them laying beautiful hard-shelled eggs again in no time. A few odd eggs here and there are normal too.

With a little detective work and some adjustments to their care, your flock’s egg quality will be back to normal before you know it. So don’t stress over the occasional soft egg – just focus on keeping your chickens healthy and happy. They’ll repay you in perfect eggs for years to come.